Effects of Reduced Crude Protein and Fiber Supplementation on Nitrogen and Phosphorus Utilization and Availability

Purdue University 2003 Swine Research Report. In recent years, animal agriculture has been surrounded by concerns of environmental contamination and degradation. To reduce potential environmental hazards, researchers have tried various practices to reduce the amount of nutrients being excreted in swine manure and ammonia emissions from manure contributing to diminishing air quality. To prevent further environmental concerns, diet modification has become an alternative to reduce unutilized dietary nitrogen (N) and phosphorus (P). It is known that as a pig grows, feed intake increases while protein and phosphorus requirements decrease (Pond et al., 1995). To meet these changes in nutrient needs, producers use phase feeding techniques to balance the dietary nutrient concentrations with the nutrient requirements of the pig. Despite this, inefficiencies still exist in the ability of the pig to digest and retain nutrients from formulated diets, with pigs only retaining approximately 56% of the amino acids they consume (NRC, 1998). In this study, reduced crude protein (CP)/high available phosphorus (HAP) corn diets were used along with normal corn/SBM diets to determine their effects on fecal and urine nutrient excretion and total manure production. Wheat bran (WB) was also added to the diets (0 or 10%) to determine the ability of fiber supplementation to sequester ammonia-N and influence changes in manure nutrient content and manure N and P forms during storage.